Albert Barnes Commentary Micah 4:6

"In that day, saith Jehovah, will I assemble that which is lame, and I will gather that which is driven away, and that which I have afflicted;" — Micah 4:6 (ASV)

In that day - that is, in that day of Christ and of His Gospel, of grace and salvation, the last days of which he had been speaking. Until now he had prophesied the glory of Zion, chiefly through the coming in of the Gentiles. Now he adds how the Jews would, with them, be gathered by grace into the one fold during that long last day of the Gospel—at its beginning, during its course, and completely at its end (Romans 11:26).

Her that halteth - The prophet resumes the image of the scattered flock, under which he had previously foretold their restoration (Micah 2:12–13). This was not his own hope, but His word, who cannot fail. The course of events he is now addressing would, at times, because of their greatness and difficulty, be beyond human belief. So he immediately adds, at the outset, saith the Lord.

To 'halt' is used of bodily lameness (Genesis 32:32), and, in the case of a flock, of being worn out by its wanderings (Zephaniah 3:19). It is also used of moral 'halting' (Psalms 35:15; Psalms 38:18), such as had been a chief sin of Israel: serving partly God and partly Baal—God with a service of fear, and Baal with a service of that counterfeit of love, sensuality. So it was sick, both in body and soul, and also driven out and afflicted.